<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style type="text/css">
        .box {
            background-color: rgba(255, 255, 255, 0.3);
            border-radius: 5px;
            font-family: sans-serif;
            text-align: center;
            line-height: 1;
            -webkit-backdrop-filter: blur(10px);
            backdrop-filter: blur(10px);

            padding: 20px 40px;
            width: 200px;
            height: 200px;
        }

        html,
        body {
            height: 100%;
            width: 100%;
        }

        body {

        }

        .container {
            align-items: center;
            display: flex;
            justify-content: center;
            height: 100%;
            width: 100%;

            background-image: url(https://i.picsum.photos/id/1080/6858/4574.jpg), linear-gradient(rgb(219, 166, 166), rgb(0, 0, 172));
            background-position: center center;
            background-repeat: no-repeat;
            background-size: cover;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="box">
            <p>backdrop-filter: blur(10px)</p>
        </div>
    </div>
</body>
</html>